Someone who makes an arse of them self, either by a stupid act , lack of an act, or just looks stupid.

1) Hey man, you see Beckham in the the game last night?
2) Yer, he missed that open goal from like a yard out.
1) I know, what a fucking tit.
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1) Check out Dave, that girl is all over him.
2) Bloody hell, lucky bastard... too bad he doesn't know it.
1) Tit
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1) Hey, check out that fucking reprobate with the girls jeans.
2) Does he have no nuts?
1) Fucking doubt it... fucking tit.